<?php
$s='I\'m a student\\teacher.';
echo $s,"\n";
$s="He say:\"I'm a student.\"";
echo $s,"\n";

$a='计算机123';
printf("[%d] [%5d] [%05d] [%x] [%5x] [%05x]\n",26,26,26,26,26,26);
echo strlen($a),"\n";
echo ord('0'),"\n";
echo ord('0123'),"\n";
echo substr($a,3),"\n";
echo substr($a,6,4),"\n";

for ($i=0,$l=strlen($a);$i<$l;++$i){
    printf("%02x",ord(substr($a,$i)));
}
echo "\n";
echo ord(substr($a,0)),"\n";
$b="\xE8\xAE\xA1\u{7B97}\u{673A}";
echo $b,"\n";

$s=<<<'XXXXYYYY'
    <?php 
    //php支持多行字符串
    $s='I\'m a student\\teacher.';
    echo $s,"\n";
    $s="He say:\"I'm a student.\"";
    echo $s,"\n";
XXXXYYYY;
echo $s,"\n";

$go='去';
$good='好的';
echo "go的意思是：$go\n";
echo "good的意思是：$good\n";
echo "good的意思是：{$go}od\n";
echo "good的意思是：“{$good}”的意思\n";

$a=[90,'php'=>98,'age'=>18];
echo "a[0]=$a[0]\n";
echo "a['php']=$a[php]\n";
echo "a['age']={$a['age']}\n";
